The present invention relates generally to EDM (electrodischarge machining) or ECM (electrochemical machining) and more specifically to a perforate tool electrode which can be used for plunge drilling, side milling, and end milling.
Electromachining processes such as electrochemical machining (ECM) and electrodischarge machining (EDM) and their combinations use electrically-conductive electrodes, for example, electrode 10 shown in FIG. 1. With this type of machining, it is necessary to flush the machining zone with a fluid medium 12. In ECM this fluid medium is an electrolyte while in the case of EDM it is a dielectric fluid. The fluid medium 12 is induced to flow past the electrode/tool 10 and the surfaces of the workpiece (WP) undergoing electro-erosion (with EDM) or electrochemical dissolution (with ECM).
Uniform and adequate flushing is needed to replenish machining zones with fresh medium and to carry away heat and sludge. Flushing accordingly has a direct effect on electromachining performance. When high speed electromachining is pursued, inadequate flushing tends to lead to process instability and limits the achievable metal removal rate.
When a conventional solid electrode is used, working medium flushing is carried out by using an external nozzle or using flow channels specially designed to introduce the medium to machining zones. Conventional external nozzles or flow channels may not be sufficient in some high speed machining applications.
A first aspect of the invention resides in an electromachining device comprising: a perforated electrode through which a fluid is discharged.
A second aspect of the invention resides in a method of electromachining comprising the steps of: passing a flow of fluid through a perforated electrode; moving the electrode into a work piece so that the flow of fluid provides an adequate amount of medium uniformly over the entire desired machining zones to ensure high speed, stable electromachining of material from the work piece.
A further aspect of the body resides in an electrode for electromachining comprising: a body; a passage structure formed in the body; and holes formed in the peripheral surface of the body through which fluid from the passage structure can flow.